DETROIT (AP) — Tesla CEO Elon Musk donated about 5 million shares of company stock worth roughly $5.7 billion to an unidentified charity in November, according to a regulatory filing.

The shares were donated from Nov. 19 to Nov. 29, the filing with the U.S. Securities and Exchange Commission said.

In late October, Musk, the world's richest man, tweeted that he would sell $6 billion in Tesla stock and give the money to the United Nations World Food Program if the organization would describe how the money would solve world hunger. But the filing did not name any recipients for the donation.

David Beasley, WFP executive director, said in a statement Tuesday that the organization hasn't received anything from Musk yet. "There are millions of people around the world on the brink of starvation. Whether WFP receives any of this money is yet to be seen, but I am excited to hear that Elon is engaged. This is an amazing and great first step," Beasley said in a statement sent by a spokesman.

A message was left Tuesday seeking comment from Tesla.

In a separate filing, Musk reported that as of Dec. 31 he holds 231.7 million shares of the electric vehicle and solar panel maker's stock, or 21.2% of the company's total value. The amount includes 172.6 million shares held by Musk's trust and options to buy another 59.1 million shares within 60 days of Dec. 31, 2021.

Last November, Musk began selling shares, which he said on Twitter would go to pay for his tax obligations on stock options that are part of his all-stock compensation package. Analysts estimate his tax obligation at $10 billion to $15 billion.

So far he has sold more than 15 million shares worth roughly $16.4 billion. Musk had written on Twitter that he would sell 10% of his stake in the company. With the sales in late December, Musk is close to selling 10%.